1. Field of the Invention
The present invention relates to a porous body of polysaccharide or polysaccharide-clay composite as a material compatible with the global environment, and a process for its production.
2. Discussion of Background
Heretofore, plastic materials such as foamed styrols (polystyrenes) or styrene papers, have been widely used as shock-absorbing materials, heat insulation materials or sound-absorbing materials, since they are light in weight and inexpensive.
However, such conventional plastic materials are made of petroleum extracted by a man power from a deposit deep in the earth's crust, and they are typical materials which cause pollution to the global environment in such a way that at the time of incineration after their use, they produce a high temperature heat to damage incinerators and generate a large amount of CO.sub.2 gas. Further, such plastic materials are likely to cause pollution to rivers or sea shores when left without being incinerated. To avoid such pollution to the global environment, a study is being conducted on readily degradable plastic materials such as biodegradable or photodegradable plastic materials.
However, up to now, there has been no material which is satisfactory for practical use, and it is still desired to develop a material which can be substituted for conventional plastic materials.